Aside: Excellent shading on the bottles to give the 3D effect in your diagram! How did you accomplish it?

I would suggest that you add a valve to inhibit the flow of water. Most water pumps would push hundreds of times more water than is necessary for two plants. If your bottles are filled with expanded clay, you probably want to add a timer to make the water pump run one hour on, one hour, off all day.

I would use a pump which power is 550 liter per hour. I think that yes it may be too powerful and I should use a valve. Did I understand you correctly that I should turn my pump on for a hour and then off for hour and the on and so on? But if I use the pump for one hour isn't the clay going to get too wet? And if I turn it off again for hour won't it dry out?
By the way I used a Google SketchUp software to make it.

Still waiting for some advice.

Hi Tom, unless you plan to expand the system, I don't think you will need a pump. I have used expanded clay in the past and have had very good results with it. One reason is that it drains very well and the downward motion of the moisture will pull plenty of fresh air down to the roots. If your system is to remain small, you could consider using a simple bubler system to raise the nutrients up fron the resivoir to the surface of the growing medium. However, you might also consider a wicking system that requires no pumps and makes the system portable. One other possibility would be to consider using a tote box and a liner made from landscaping material. It is a very inexpensive and easy to make system. The basic idea is ti install a liner inside a tote box made from landscape fabric. It allows moisture through but blocks roots from growing down into the nutrient resivoir. The liner bottom extends down into the resivoir several inches allowing the nutrients to wick up into the upper area where the plant is growing. If you care to see the units I have just built ( at a cost of about $5 dollars each), you are welcome to visit my website and look for the link to my new low cost grower project. Good luck, chuck

Here is a link that might be useful: My hydro projects

Actually I think this system for 2 plants is too small, so I think that I'll make it for 4 plants. I would still like to use a pump beacuse I think then it's much easier for me.
So I gonna need to buy some pipes. What kind of material they should be made of? Are copper pipes okay to use?

Chuck:
The only problem I see with your dirt-in-a-box system, is there is no way for the extra 3" of water in the bottom of the box to be used. the project you based yours on (josho.com or something like that) used a large net pot so the soil would go all the way down to the bottom and thus allow all the water to be wicked up into the soil. Other than that I like the idea.
tommilak:
I think your system will work just fine. a little elaborate maybe, but it'll get the job done.

I also nade a new sketch war for 4 plants. May I use copper pipes for this system or not? What should be the diameter of the pipes? On h sketch it is 1cm.

{{gwi:1004056}}

Don't use copper. If you insist on using metal use brass.
But really you should look at using a plastic pipe. they're much easier to cut to length. modify.
I would size the pipe to fit your pump. I mean a 3/4 dia pipe isn't going to easily fit onto most smaller pumps.

Read some fluid mechanics for sizing of pipes.

Use PVC pipe, it's less expensive and easier to fabricate and has NSF approval. Metals and chemicals are a bad mix for food crops.

Here is a link that might be useful: Fluid Mechanics

No advice on how to make that cool shading in your graphics? Grr.

I'm going to have to disagree with will and the grizz though. Use copper whenever possible. PVC is adequate when in a pinch, but nothing is as permanent as copper. It's the greatest medium for piped liquids ever. 1/4" or even 1/8" will be plenty wide enough for your 4 plant system.

copper may be more permanent, but conversely there is no room for modification / adjustment if you don't cut it right. also, there has to be a reason copper isn't used in water lines while pvc is?

Because copper is a whole heck of a lot more expensive than PVC? When I was growing up, we had copper pipes. When we finally had to replace them, copper was not an option because it was cost-prohibitive!

The reason to use copper or not has nothing to do with perminance or cost!!!!!!!!!!
Don't use copper or any other metal (except stainless steel) in hydroponics or aquaponics. It is because the salts in the nutrients can react with the metals and cause all sorts of corrosion and nutrient imbalances. In Aquaponics, something like copper plumbing can kill the fish.

Oh, I'm so stupid :( I already bought copper pipes before reading your advice. I still think that I have to use these pipes, because it's almost ready (my system).
Maybe someone can still give me some advice. I have to put something at the ond of the pipes to spread the water so it could run evenly. But I don't know what to use. Can someone help me?

Any advice?

Cap the ends of the pipes. drill some small holes in the top where you want the water evenly distributed. If the pipe is level, once it fills water will come out all the holes in a fairly uniform distribution.
If you need a round distribution, put a "T" joint in, make a loop with vinyl hose and drill as described above.

Hi.
I bought today the nutrients for my tomatoe plats but I don't know if I bought the right thing. On the bottle it is said that it's ment for hydrocultures but also it is said that it's for plants that don't bloom. The elements in it are:
N - 4,0%
P2O5 - 5,0%
K2O - 6,0%
B - 0,018%
Cu - 0,009%
Fe - 0,034%
Mn - 0,018%
Zn - 0,0018%
Can anyone tell if this fertilizer will work for my tomatoe plants?

Should I buy something better or maybe I should mix nutrients by myself using this page: http://ag.arizona.edu/hydroponictomatoes/nutritio.htm

I don't know why people don't mix there own nutrient. It's simple and a lot cheaper.

I wouldn't say that it's simple. If I want to make everything right I need to put every elemet exactly and the right weight is about under 1 gram. And I don't have no idea where to get these elements.

tommilak wrote:
I wouldn't say that it's simple. . .

Of course it is! I've been doing it for years. But buy the micro-nutrients on-line, 'cause that's just too much hassle to make yourself. The rest is fairly straightforward, although you DO need a scale 0-100g.

Years ago I couldn't get micro-nutrients, so I burnt wood to make ash which I dissolved in nitric acid in order to recover the micro-nutrients in the wood. Did that for years.

To tommilak,

I am a ticketed, licensed plumber and I believe you should get away from plastics AS MUCH AS YOU CAN. PVC, CPVC, and PEX are chlorinated poly vinyl. They will leech at the start and then rinse out o.k however after exposure to U.V light (grow lights) they will start to break down. Check your solder and make sure that it is lead free (by law) use as little flux as possible but FLUSH your system for at least a week. I use a strong lemon juice concentrate (acidic) and let it run for a week. As for copper leeching, copper is used by the body and is a natural element. Your nutrient mix contains copper! One thing I discovered on one of my first systems was hydro static electricity. Moving water will generate a tiny, tiny amount of an electrical charge. Quick fix, bare copper wire wrap it around your copper somewhere and ground it, the copper on copper contact will remove the charge. Copper is a little pricy, get to know your scrap yard guy or local dump person, with some beer and a little luck, you can get scrap that is easy to clean and re-use. My first system is 4 years old and still going strong, I notice no difference in taste or texture of my fruits and veg. Good Luck!